tf.io.decode_image
Function for decode_bmp, decode_gif, decode_jpeg, and decode_png.
tf.io.decode_image(
contents, channels=None, dtype=tf.dtypes.uint8, name=None,
expand_animations=True
)
Detects whether an image is a BMP, GIF, JPEG, or PNG, and performs the appropriate operation to convert the input bytes string into a Tensor of type dtype.
Note: decode_gif returns a 4-D array [num_frames, height, width, 3], as opposed to decode_bmp, decode_jpeg and decode_png, which return 3-D arrays [height, width, num_channels]. Make sure to take this into account when constructing your graph if you are intermixing GIF files with BMP, JPEG, and/or PNG files. Alternately, set the expand_animations argument of this function to False, in which case the op will return 3-dimensional tensors and will truncate animated GIF files to the first frame.
| Args |
|---|
contents | 0-D string. The encoded image bytes. |
channels | An optional int. Defaults to 0. Number of color channels for the decoded image. |
dtype | The desired DType of the returned Tensor. |
name | A name for the operation (optional) |
expand_animations | Controls the shape of the returned op's output. If True, the returned op will produce a 3-D tensor for PNG, JPEG, and BMP files; and a 4-D tensor for all GIFs, whether animated or not. If, False, the returned op will produce a 3-D tensor for all file types and will truncate animated GIFs to the first frame. |
| Returns |
|---|
Tensor with type dtype and a 3- or 4-dimensional shape, depending on the file type and the value of the expand_animations parameter. |
| Raises |
|---|
ValueError | On incorrect number of channels. |